With the development of instant messaging (IM), the IM has been widely accepted by most internet users, and has become an indispensable tool not only in daily entertainment but also at work. Therefore, more demanding requirements on usability, reliability, security, and many other areas are introduced by users. There are various types of information in an instant messaging software, and users pay attention to certain information differently. For example, if information about friends in SNS community is updated, only some of the users are interested about this update. Such update does not necessarily need to be updated instantly.
Conventionally, there are two solutions for pulling the updated information. First, updated information is pulled from the server when the client side logs in. With this solution, once the user logs in, the client side will not be able to update newly added information after logging in, which greatly affects the user experience. Second, the updated information is regularly pulled from the server by the client side. In this second solution, it is difficult to set the time interval for updating information, as it varies according to different user needs. Some of the users may not care about certain data, but the updated information is pulled for too many times which consumes internet bandwidth, while some other users who may care about this data may not receive the updated information in a timely manner.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.